development and evaluation of a virtual reality patient

Simon Nestler, Manuel Huber, Florian Echtler, Andreas Dollinger, Gudrun Klinker

Development and Evaluation of a Virtual Reality Patient Simulation (VRPS)

Introduction

During disasters, paramedics cope with numerous tasks- Establishing organizational structures- Triaging all involved patients (45s per patient)- Medicating the patients according to their injuries

NATO Triage Standard

Triage category Treatment

T1 Immediate Treatment

T2 Delayed Treatment

T3 Minimal Treatment

T4 Expectant Treatment

2Development and Evaluation of a Virtual Reality Patient Simulation

Introduction

3

Triage based on the mSTaRT-algorithm:- Check whether the patient is able to walk- Test the patient for deadly injuries- Check and count out breathing rate- Apply compression bandages on serious bleedings- Feel the patient’s peripheral pulse- Check if the patient is awake and responsive

2006

Germany

Triage by doctors

Germany

Triage by doctors

Munich

Triage by paramedics

Germany

Triage by paramedics

Present day ?

K. Kanz, P. Hornburger, M. Kay, W. Mutschler and W. Schäuble: mSTaRT-Algorithmus für Sichtung, Behandlung und Transport bei einem Massenanfall von Verletzten, Notfall Rettungsmed. (2006) 264-270

Development and Evaluation of a Virtual Reality Patient Simulation

Motivation

4

Recent introduction of new triage procedures requires intensive and continuous training

Large scale disaster control exercises are expensive and laboriousSmaller trainings offer only limited training possibilities Triage trainings have to be optimized regarding..

- Affordability (number of exercise actors)- Intensity (number of triage processes)- Realism (actor make-up, environment) Affordability

Realism

Intensity


Motivation

5

Advantages of computer-based triage trainings:- Low lead time - Scalable- No actors required- No organisational overhead

Advantages of multi-touch table top interfaces:- Intuitive interaction- Two-handed interaction- Collaborative interaction


Designing virtual patients

6

Gutsch et al. presented a desktop computer-based triage simulationFor continuous training of paramedics their approach is insufficient:

- No collaboration- No interaction metaphors- “Multiple-choice” training- No two-hand interactions- No possibility to make mistakes

W. Gutsch, T. Huppertz, C. Zollner, P. Hornburger, M. Kay, U. Kreimeier, W. Schäuble and K. Kanz: Initiale Sichtung durch Rettungsassistenten. Notfall Rettungsmed., 9(4):384-388, 2006.


Technical background

7

Multi-touch technologies have first been presented by Lee et al. Our multi-touch table top is based on the technology of Jeff Han

Multi-touch sensing through frustrated total internal reflection

S. Lee, W. Buxton and K. Smith: A multi-touch three dimensional touchsensitive tablet. In CHI '85: Proceedings of the ACM Human Factors in Computing Systems Conference, San Francisco, California, USA, 1985.

J. Han. Low-cost multi-touch sensing through frustrated total internal reflection. In UIST '05: Proceedings of the 18th annual ACM symposium on User interface software and technology, pages 115-118, New York, NY, USA, 2005.

77Development and Evaluation of a Virtual Reality Patient Simulation

Implementation

8

- Removing foreign bodies- Performing the head tilt-chin lift

manoeuvre and looking for foreignbodies

- Checking the patients’ breathing

Paramedics are familiar with the basic procedures

Red boxes are not visible duringtriage training


Implementation

Changing patient position- Propping up the patient- Putting down the patient


Implementation

10

Allocation of coloured patient tags- Select patient tag (hand 1)- Apply it to the patient (hand 2)


Patient model

11

General behaviour of patients can be described by state machines

General interactions- Touch- Check breathing- Take pulse- Check bleeding- Assign card


Patient patterns

12

Concrete patient information is contained in specific patient patterns(= additional state transitions)

More than 300 different patient patterns have been designed by the fire department Munich

Patient model and patient patterns have to be combined, resulting in a single large state machine


Evaluation

13

Comparison to real-life triage trainings:time per triage process

Average time for one triage process is about half as long as in real disastercontrol exercises (22s vs. 41s)



Evaluation

14

Quality of triage processesComparision of results to real-life triage trainings

In the real-life disaster control exercise about 85 percent of all patients were triaged correctly, in the table top training 89 percent of all patients were triaged correctly => no significant difference.



Conclusion and future work

15

VRPS does not prevent inaccurate triage decisionsRetaining the possibility to make errors is importantTable top device is adequate to be used in disaster control exercisesMore frequent trainings of the paramedics can improve preparedness for

real disasters

Training effects will be the topic of our future workThree groups of paramedics: the first group trains on the table top, the second one performs no training and the third one trains with real mimes

Acknowledgements:Mr. Tretschok Paramedics from Munich fire department


development and evaluation of a virtual reality patient

Documents